Retina MacBook Pro (Mid 2012) only charging with 60W adapters, not with 85W adapters

[mav2010]

Hi,

I have a strange issue with my Retina MacBook Pro (Mid 2012). One day it suddenly stopped charging (green led on Magsafe not on and also no power adapter recognized in system profiler) with both my original Apple 85W chargers. With one of them I can make it charge again by unplugging and replugging the charger cable like 20-30 times. I tried all the usual things (cleaning the Magsafe port, PRAM reset, SMC reset, battery unplugging etc.), but to no avail.

What is super strange: I have a 60W rated China USB-C to Magsafe adapter that I use together with an original 87W charger from my other, newer MacBook Pro - and that is working COMPLETELY fine. It charges immediately when plugging in every time and this charger/adapter combination is correctly identified as a 60W charger.

Any ideas what I could still try to make the original 85W chargers work again? If you need any more information, please let me know!

Thanks,
Max

 

[Fishrrman]

My advice:

The 2012 is getting a little longer-in-the-tooth now.
If you have a charger that works, and one that doesn't...
then
Use the one you have THAT WORKS, and be happy (even if it charges the MPB a little more slowly).

It might be the small board that controls charging and power inside the MPB.
Don't know.
It could be something else.
It would probably cost you money to find out what, and repair it.
That's why... just keep using "what works".

Again, my opinion only.

 

[mav2010]

I completely agree. The reason for asking here is mainly out of curiosity and/or inconvenience.

However, since it is a model with almost all the upgrades, it would be very sad. The machine is still more than enough for an everyday casual use notebook at home (and even more). Even the battery is still in very good condition.

I have ordered a new MagSafe DC in board that I will put aside if the 60W charging solution stops working. Then I will try to switch the DC in board and cross my fingers that this fixes the issue. If not, it must be the logic board and a repair would not pay off anymore.

 

[ZeitGeist]

The MagSafe port/connector is a discrete component inside the MacBook - ie it can be swapped out by itself, without needing to replace the motherboard or anything like that.

It isn’t too expensive a component to buy and replace, if you are mechanically adept.

 

[mav2010]

I know - I already ordered the replacement DC IN board (for $20). However, I will only attempt to switch it, when my current workaround charging solution stops working. The risk of ruining the MacBook completely is just to high for me.

But why would the charging work rock solid with a 60W charger and not at all with a 85W charger. This is what I don't understand at all... it must be the higher voltage / current of the 85W charger that is causing the charging process to fail. Does anyone have insights on how exactly the SMC determines what type of charger is attached?

 

[smbu2000]

Have you tried cleaning the physical magsafe connectors on MBP? It might just be some dirty contacts. On my old rMBP, I had a charger that would only charge one way and not the other (shouldn't matter which way you plug it in) and after cleaning the MBP and the charger connector with a q-tip and IPA, then it worked fine again. Might not help, but it is worth a try anyway.

 

[ZeitGeist]

I know - I already ordered the replacement DC IN board (for $20). However, I will only attempt to switch it, when my current workaround charging solution stops working. The risk of ruining the MacBook completely is just to high for me.

But why would the charging work rock solid with a 60W charger and not at all with a 85W charger. This is what I don't understand at all... it must be the higher voltage / current of the 85W charger that is causing the charging process to fail. Does anyone have insights on how exactly the SMC determines what type of charger is attached?

It’s not the SMC. Discrete circuitry on the DC in board is most likely fading or one of the identifying pins (that identifies voltage) is broken or corroded. That’s consistent with what you are seeing.